1. Field
The following description relates to a matching module.
2. Description of Related Art
With the recent development of mobile communication systems, mobile devices are rapidly spreading. Accordingly, demand for miniaturization and high performance in a large number of electronic parts used in mobile devices is increasing. Among such electronic parts, a duplexer is responsible for functions of separating a transmitting signal and a receiving signal. and simultaneously extracting only a signal of a necessary frequency band. A duplexer is an essential component in a transmitting/receiving communication method such as an analog or Code Division Multiple Access (CDMA) method.
Such a duplexer includes a transmitting filter, a receiving filter, and a matching module for separating a transmitting signal of the transmitting filter and a receiving signal of the receiving filter. The matching module separates the transmitting signal and the receiving signal to minimize interference between the transmitting signal and the receiving signal. The matching module is configured to minimize an influence on electrical characteristics of the transmitting filter and the receiving filter. For example, the matching module may be represented as an equivalent circuit in which a capacitor-inductor-capacitor is connected in a form of a pi (π) filter. In order to change a phase while maintaining a matched frequency band of the matching module, capacitances of two capacitors may need to be the same. However, there may be a problem in that the capacitances of the two capacitors are possibly different due to a parasitic capacitance incidentally generated in the matching module.